Refrigerator closure



p 24, 1940- i F. w. KNOWLES I 2,215,964

REFRIGERATOR CLOSURE Filed May 1, 1939 INVENTOR. Frank W Know/es ATTORNEY.

Patented Sept. 24, 1940 UNITED STATES PATENT. OFFICE 2,215,964 REFRIGERATOR. CLOSURE Frank W. Knowles, Seattle, Wash. A plication May 1, 1939, Serial No. 271,070

7 Claims.

The present invention relates to the construction of refrigration chambers. In more particular, the present invention relates to a closure for a refrigeration chamber and to means for preventing the frosting and sticking or locking of such a closure due to the accumulation of ice and frost thereon.

In those refrigerated chambers where materials are being continuously passed in and out for processing, it -is very desirable that very little of the cold air of the chamber or of the warm air outside of the chamber pass through the entrances or exits of the chamber. If his attempted to closely fit a door or series of doors in an entrance of a refrigerated chamber, the doors rapidly collect frost, and often times in a few minutes they will stick and fail to function properly.

It is an object of the present invention to provide means for preventing the frosting or icing of the doors, or closures, of refrigerated chambers.

It is a further object ofthe present invention to prevent the frosting or icing of the doors, or closures, of refrigerated chambers by supplying heat to such closures or to the structure adjacent the closures, in sufllcient quantity to prevent the injurious formation of frost or ice on or adjacent such closures.

It is a further object of the present invention to devise a closure that will at all times seal the entrance to a refrigerated chamber, will allow the ready passage of material through the entrance, and which closure will not frost.

It is a further object of the present invention to devise a closure comprising a series of chambers mounted for rotation about an axis and forming a closure and means for feeding material to a refrigerated chamber, and to devise a means for heating such a closure to prevent the formation of ice on and adjacent thereto.

It is a further object of the present invention to provide a closure for a refrigerated chamber, and to provide means formaintaining the temperature of said closure at a constant value.

These objects and others are obtained by forming an entrance to a refrigerated chamber and placing in that entrance 9. series of sections that are radially mounted about an-axis to form a socalled revolving door, or air-lock. The sections of this closure are hollow and adapted to receive hot water or steam supplied from any suitable source through the trunnions upon which the sections are supported; Any suitable means may supply power for rotating the closure upon its axis. A thermostatic valve is mounted on the outlet to regulate the temperature of the water leaving the closure and hence the temperature of the closure. Also, the thermostatic v'alve, by regulating the temperature, prevents the freezing of 5 the water in the closure. The entrance sides are shaped like two opposed parts of a cylinder in order to closely fit the rotating closure and to insure that cooperating sections will at all times closethe entrance.

As the closure is rotated, material is fed into the closure and passed into the chamber. The heating of the closure reduces condensation thereon andprevents the freezing of any moisture that may condense upon the closure. In most instances the closure will radiate enough heat to the adjacent entrance wall to prevent condensation thereon. If necessary the entrance wall may also be heated. In some instances it may be suflicient to heat only the entrance walls.

In the accompanying drawing there is illustrated a device for accomplishing the above objects, which device is constructed as above-out lined, and in which drawing:

Figure 1 is a perspective view, partly broken, of a refrigerated chamber having closures embodying the present invention.

Figure 2 is a longitudinal section of one of the entrances and closures shown in connection with Figure 1.

In Figure 1, the device illustrated in this figure comprises chamber l which may be insulated in any desired manner, and in which is. located a conveyor 2 driven by any suitable means, for conveying thru the chamber material which it is desired to treat. The chamber may be refrigerated by any suitable means. Adjacent one end of the conveyor and in top of the chamber is an entrance 3 thru which material is passed into the chamber for treatment upon the conveyor, and adjacent the other end of the conveyor and in the bottom of the chamber is an exit 4 thru which material is passed out of the chamber after treatment therein.

In both the entrance and the exit may be placed the same type of closure, which closure forms the subject-matter of the present invention. A hopper Ill receives the material to be fed into the chamber. From :the hopper the material falls into one of the chambers formed by the closure II. The closure is made up of a plurality of sections l2, l3, I4 and I5 that are arranged radially about an axis formed by the hollow trunnions l6 and l1. '1'he sections are hollow and in communication with the bore of I the trunnions. The trunnions are mounted for rotation in the bearings l8 and IS. A casing 20 connects the hopper with the chamber and forms a housing for the closure and a passageway for the refrigerated chamber. The casing is cylindrical in form, the sides of it being, in form, opposed parts of the sides of a cylinder. The hopper and closure casing may be suitably insulated to prevent condensation thereon. The casing 20 may be considered as part of the construction forming the entrance to the refrigerated chamber. Material passing thru the closure drops upon the plate 2| and from there it slides out upon the conveyor.

The closure is rotated by means of a pulley 22 mounted upon the hollow trunnion II. The pulley may be driven thru a belt by a suitable motor 23. Coupling units 24 and 25 allow the trunnions to rotate while the pipes 28 and 21 which bring the hot water to and from the trunnions and closure remainstationary. Connected in the inlet pipe 28 isja valve 28 for shutting off the flow of water to the closure. In the outlet pipe there is connected the thermostatic valve 29 which may be set to control the temperature of the waste water from the closure.

Operation of the device is as follows: The chamber l is refrigerated by any suitable means and to'any required degree, and the conveyor 2 is driven by any suitable means. The thermostats 29 of the entrance and exit closures are set at a temperature that will prevent the formation of frost upon the closures. This temperature may behigh enough to prevent condensation or only high enough to prevent freezing. The closures are set in rotation by the motor 23 driving the pulley 22. The feed and waste pipes do not rotate as they are freely coupled to the trunnions through the coupling and packing ,units 24 and 25.

Material placed in the hopper III will pass into one of the compartments formed by the sections l2, l3, l4, and I5, be sealed oil from the exterior and interior of the chamber 1 by a partial rotation of the closure, and upon further rotation of the closure will fall and pass into the chamber I and down upon the plate 2|. From the plate 2| thematerial will slide on to the. conveyor 2. when the material comes to the end of the conveyor as the conveyor passes around its and drum, the material will fall into the hopper of the exit closure where the process of passing the material out of the chamber will be performed in the same manner as for bringing it into the chamber as the two closures may be identical. The rate of feeding material to the conveyor may be governed by the speed of rotation of the entrance closure. The hollow sections of the closure may have bailes therein to aid in the distribution of the hot water therethru.

The present invention may take other forms than the rotary closure shown. The closure may take the form of a series of spaced apart hollow sections disposed transversely of an entrance duct. The individual sections may be heated by conveying hot water to and from them through flexible conduits. To pass material, the sections are linked together and so operated that they move transversely of the duct and that one section closes the duct before another one is moved to open it.

Also, instead of heating the closure, the frame. or casing, for the closure may be heated. This will prevent the formation of ice on the housing and will lessen the formation of ice on the clo-- sure. If the formation of ice is heavy, rapid, it

may be desirable to heat both the closure and its housing.

, As used in the claims hereinafter, the word "entrance is intended to cover both an entrance and an exit.

Having thus described my invention, I claim: 1. A seal for a refrigerated chamber, comprising: means forming a passageway for a refrigerated chamber, means forming a series of chambers adapted to be rotated about an axis and acting as a closure for said passageway, and means for heating said closure to prevent the formation of frost thereon and to allow for its easy rotation.

2. A seal for a refrigeration "chamber, comprising: means forming a passageway for a refrigeration chamber, a series of closures for said passageway, and means for heating said closures to prevent the formation of frost thereon and to allow for their easy movement.

3. A seal for a refrigeration chamber, compris ing: means forming a passageway for a'refrigeration chamber, a plurality of sections arranged in successive positions across the path of travel through said passageway, means for moving said sections to allow the passage of material thru said passageway, and means for heating said sections to prevent the formation of frost thereon and to allow for their easy movement.

4. A seal for a refrigerated chamber, comprising: a hollow tunnion, and a plurality of hollow sections arranged radiallyabout and supported by said trunnion; said sections extending equal radial distances from the axis of said trunnion,

and the hollows in said trunnion and said sections being arranged for the conduct therethru of a heating fluid.

5. A seal for arefrigerated chamber, compris ing? a trunnion, anda plurality of sections arranged radially about and supported by. said trunnion, said sections extending equal radial distances from the axis of said trunnion, and means for heating said sections.

6. A seal for a refrigeration chamber, comprising: means forming a passageway for a eration chamber, a closure in said m and said closure being smaller than said eway, and means for heating said closure.

7. A seal for a refrigeration chamber, comprising: a passageway and a closure therefor, said passageway and said closure having cooperating sealing surfaces with a sliding relationship between said surfaces, and heating means for said surfaces.

FRANK w. mom-as.

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